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PTC Creo ModelCheck Teacher: Datum Features
Datums are non solid geometric objects that are used as construction features to help model other features and assemble components. The major different types of datums are:
Planes
Coordinate Systems
Axes
Curves
Points
There are several key rules to follow when using datums:
Always start new parts and assemblies with default datum planes and coordinate systems.
If you do not need a datum, delete it, it is overhead to your model.
If Creo ModelCHECK complains that there is a datum plane that has only one parent that is also a datum plane, do the following:
Redefine the children so that they reference the parent datum plane.
Delete the datum plane.